feat: add cover image functionality for articles

- Implemented `resolveApiURL` function to handle various URL formats.
- Updated `ArticleDetail` and `UpdateArticleRequest` interfaces to include `cover_asset_url`.
- Enhanced `ArticleEditorView` to manage cover image uploads, including a new `CoverPickerModal` component.
- Added cover image requirements logic in `cover-requirements.ts` to enforce platform-specific cover image rules.
- Modified backend services to handle cover image uploads and validations, including checks for required cover images for specific platforms.
- Improved error handling for cover image requirements during article publishing.

server/internal/tenant/app/article_service.go

@@ -263,6 +263,7 @@ type ArticleDetailResponse struct {
 	TemplateName           *string                `json:"template_name"`
 	GenerationMode         *string                `json:"generation_mode"`
 	Platforms              []string               `json:"platforms"`
+	CoverAssetURL          *string                `json:"cover_asset_url"`
 	GenerateStatus         string                 `json:"generate_status"`
 	PublishStatus          string                 `json:"publish_status"`
 	Title                  *string                `json:"title"`
@@ -310,6 +311,7 @@ func (s *ArticleService) Detail(ctx context.Context, id int64) (*ArticleDetailRe
 	}
 	d.GenerationMode = resolveArticleGenerationMode(dbSourceType, inputParamsJSON)
 	d.Platforms = resolveArticlePlatforms(wizardStateJSON, inputParamsJSON)
+	d.CoverAssetURL = resolveArticleCoverAssetURL(wizardStateJSON)
 	d.WordCount = resolveWordCount(d.MarkdownContent, d.WordCount)
 	return &d, nil
 }
@@ -366,6 +368,7 @@ type UpdateArticleRequest struct {
 	Title           string   `json:"title"`
 	MarkdownContent string   `json:"markdown_content"`
 	Platforms       []string `json:"platforms"`
+	CoverAssetURL   *string  `json:"cover_asset_url"`
 }
 
 type ArticleImageUploadResponse struct {
@@ -418,7 +421,7 @@ func (s *ArticleService) Update(ctx context.Context, id int64, req UpdateArticle
 
 	wordCount := countArticleWords(markdown)
 	sourceLabel := "手动编辑"
-	nextWizardStateJSON, err := mergeArticleWizardState(wizardStateJSON, title, req.Platforms)
+	nextWizardStateJSON, err := mergeArticleWizardState(wizardStateJSON, title, req.Platforms, req.CoverAssetURL)
 	if err != nil {
 		return nil, response.ErrInternal(50012, "update_failed", "failed to update article metadata")
 	}

server/internal/tenant/app/media_service.go

@@ -456,6 +456,9 @@ func (s *MediaService) CreatePublishBatch(ctx context.Context, articleID int64,
 	if err != nil {
 		return nil, err
 	}
+	if publishBatchRequiresCover(accountSeeds) && strings.TrimSpace(pointerStringValue(req.CoverAssetURL)) == "" {
+		return nil, response.ErrBadRequest(40044, "publish_cover_required", "baijiahao publishing requires a cover image")
+	}
 
 	var publishBatchID int64
 	if err := tx.QueryRow(ctx, `
@@ -529,6 +532,22 @@ func (s *MediaService) CreatePublishBatch(ctx context.Context, articleID int64,
 	}, nil
 }
 
+func publishBatchRequiresCover(accounts []platformAccountSeed) bool {
+	for _, account := range accounts {
+		if strings.TrimSpace(account.PlatformID) == "baijiahao" {
+			return true
+		}
+	}
+	return false
+}
+
+func pointerStringValue(value *string) string {
+	if value == nil {
+		return ""
+	}
+	return *value
+}
+
 func (s *MediaService) ListArticlePublishRecords(ctx context.Context, articleID int64) ([]PublishRecordResponse, error) {
 	actor := auth.MustActor(ctx)
 	return s.listArticlePublishRecords(ctx, actor.TenantID, articleID)

server/internal/tenant/app/prompt_generate_service.go

@@ -181,7 +181,7 @@ func (s *PromptRuleGenerationService) GenerateFromRule(ctx context.Context, req
 	}
 
 	inputJSON, _ := json.Marshal(inputParams)
-	wizardStateJSON, _ := mergeArticleWizardState(nil, promptRuleGeneratingTitlePlaceholder, platformIDs)
+	wizardStateJSON, _ := mergeArticleWizardState(nil, promptRuleGeneratingTitlePlaceholder, platformIDs, nil)
 
 	tx, err := s.pool.Begin(ctx)
 	if err != nil {

server/internal/tenant/app/publish_platforms.go

@@ -78,6 +78,31 @@ func extractPlatformsFromJSONPayload(raw []byte) []string {
 	return nil
 }
 
+func resolveArticleCoverAssetURL(wizardStateJSON []byte) *string {
+	value := strings.TrimSpace(extractStringFromJSONPayload(wizardStateJSON, "cover_asset_url"))
+	if value == "" {
+		return nil
+	}
+	return &value
+}
+
+func extractStringFromJSONPayload(raw []byte, key string) string {
+	if len(raw) == 0 {
+		return ""
+	}
+
+	var payload map[string]interface{}
+	if err := json.Unmarshal(raw, &payload); err != nil {
+		return ""
+	}
+
+	value, ok := payload[key].(string)
+	if !ok {
+		return ""
+	}
+	return strings.TrimSpace(value)
+}
+
 func normalizePlatformsFromValue(raw interface{}) []string {
 	switch typed := raw.(type) {
 	case nil:
@@ -101,7 +126,7 @@ func normalizePlatformsFromValue(raw interface{}) []string {
 	}
 }
 
-func mergeArticleWizardState(raw []byte, title string, platforms []string) ([]byte, error) {
+func mergeArticleWizardState(raw []byte, title string, platforms []string, coverAssetURL *string) ([]byte, error) {
 	state := make(map[string]interface{})
 	if len(raw) > 0 {
 		_ = json.Unmarshal(raw, &state)
@@ -123,5 +148,14 @@ func mergeArticleWizardState(raw []byte, title string, platforms []string) ([]by
 		}
 	}
 
+	if coverAssetURL != nil {
+		trimmedCoverURL := strings.TrimSpace(*coverAssetURL)
+		if trimmedCoverURL == "" {
+			delete(state, "cover_asset_url")
+		} else {
+			state["cover_asset_url"] = trimmedCoverURL
+		}
+	}
+
 	return json.Marshal(state)
 }